1. Field of the Invention
The present invention relates to rugs. In particular, the present invention provides rugs that exhibit a wool-like appearance. Additionally, the invention provides processes for fabricating a wool-like rug.
2. Background of the Invention
Patterned rugs crafted from wool are highly desirable to many consumers, especially in light of the return to natural wood floors in residential and commercial interiors seen in recent years. "Antiqued" or "old" patterned wool rugs, whether aged naturally through time and wear, or fabricated to exhibit an antique-like appearance, are even more desirable, as this style approximates the appearance of an expensive heirloom piece. Such rugs are also commonly known as "oriental rugs." An "antique" rug is a rug produced more than 20 years ago. The category is further divided into "old" rugs, i.e., those manufactured at or before 1900, and "modern" rugs i.e., those manufactured since 1900.
The cost of patterned or oriental-type wool rugs is often quite high, however. For example, a true antique or old wool rug can command a price of many thousands of dollars if in good condition. Even when new wool rugs are crafted by machine-looming and/or machine-dyeing to lessen labor costs, the rugs remain expensive, due to, among other reasons, the high cost of wool which, at 1998 market prices, sells for upwards of $3.50/lb. Furthermore, raw wool requires substantial pre-processing to minimize naturally occurring defects, which further increases the final cost of a wool rug to the consumer.
Because of the high cost of wool rugs, attempts have been made to fabricate such rugs from synthetic resins, such as polyolefins, e.g., polypropylene. The pre-dye price for polyolefin yarn used to make rugs is approximately $1/lb. This difference in price translates to a final cost of $50 to $600 for a rug made from polyolefin fibers, as compared to an approximate cost of $1,500 to $4,000 finished cost for a patterned rug made from wool.
However, manufacturers have been unable to successfully duplicate the look of patterned wool rugs using synthetic fibers, such as polyolefin. One reason for this is that, as a product with naturally-occurring, inter-fiber variability, wool fiber experiences differing amounts of dye uptake even among a single lot of wool. Therefore, when differently colored wool fibers are woven into a rug, the rug will often exhibit a multitude of color variations even among fibers dyed with the same dye shade. Thus, it is common for a dyed wool rug to be comprised of very subtle shade differences throughout the product. The consumer expects such color variations in wool rugs and considers them to be more "natural looking." A naturally aged wool rug will exhibit even more natural color variation due a to loss of color intensity resulting from the aging process.
In contrast, no such natural-looking color variability has been attainable previously in rugs woven from polyolefin fibers. Fibers made from polyolefin resin are produced under controlled and reproducible chemical conditions. Pigmentation is consistent both within and among lots of fiber. Such consistency in coloration is considered by the consumer to be "unnatural-looking" and, as such, undesirable in a simulated wool rug.
In some synthetic fibers, such as nylon, a more natural-looking dyed fiber may be attained using space-dyeing techniques. Knit-de-knit space-dyeing is a technique in which fibers are knitted into a sock, color is added to the surface of the fibers by, for example, print rolls, and the fibers are deknitted to form single fibers that will have different colors dispersed somewhat randomly along the fiber length. When the multi-colored fiber is incorporated into a carpet, the coloration of the carpet will appear more random and, thus, more natural-looking. Using this technique, the random coloration possible with wool fibers may be approximated in some synthetic fibers.
However, polyolefin e.g., polypropylene fibers, are not amenable to dyeing with such methods due to the lack of reactive groups in the resin which prevents surface dyes, such as acid dyes, from adhering to the fiber. Thus, it is not possible to durably dye polyolefin fibers using space-dyeing techniques. Because of the lack of reactive groups in polyolefin fibers, the fibers arc normally colored during the extrusion process, e.g., solution dyed, which also maximizes the uniformity of color deposition throughout the fiber. This results in polyolefin having been considered an undesirable fiber-type for use in simulated wool patterned rugs.
Despite the difficulties experienced in obtaining natural-looking dyed polyolefin rugs, polyolefin remains a desirable material from which to fabricate rugs. For example, as compared to wool fibers, polyolefin fibers exhibit superior resistance to chemicals, sunlight, mildew, moisture, moths and abrasion. Further, polyolefin fibers are of lower density than wool and can be thermoset.
In light of the above, it would be desirable to be able to fabricate rugs from dyeable polyolefin fibers wherein the rugs are natural-looking and wool-like in appearance. Moreover, it would be desirable to fabricate natural-look, wool-like rugs, wherein the rugs, when dyed and woven from polyolefin fibers, exhibit a look similar to patterned or oriental-type rugs made from natural wool.